Two astronauts on spacewalk to fix ammonia leak: NASA TV

MOSCOW: NASA astronauts Tom Marshburn and Chris Cassidy on Saturday began an emergency spacewalk to try to stop ammonia from leaking from the International Space Station's power system, NASA television showed.

During the spacewalk, expected to last six and a half hours, flight engineers Marshburn and Cassidy will try to inspect and possibly repair the ammonia leak that affected the US segment of the orbiting laboratory on Thursday. (AFP)